Phenology
| Year | Migration site | First | Migration site | Last | |||||
|---|---|---|---|---|---|---|---|---|---|
| 2021 |  |
VRS Castricum | 4 April | |
VRS Castricum | 9 May | |||
| 2020 | |
VRS Castricum | 4 April | |
VRS Castricum | 14 October | |||
| 2019 | |
VRS Castricum | 4 April | |
VRS Castricum | 31 October | |||
| 2018 | |
VRS Castricum | 4 April | |
VRS Castricum | 4 November | |||
| 2017 | |
VRS Castricum | 31 March | |
VRS Castricum | 19 October | |||
| 2016 | |
VRS Castricum | 2 April | |
VRS Castricum | 26 October | |||
| 2015 | |
VRS Castricum | 12 April | |
VRS Castricum | 22 October | |||
| 2014 | |
VRS Castricum | 1 April | |
VRS Castricum | 20 November | |||
| 2013 | |
VRS Castricum | 14 April | |
VRS Castricum | 14 October | |||
| 2012 | |
VRS Castricum | 1 April | |
VRS Castricum | 20 October | |||
| 2011 | |
VRS Castricum | 26 March | |
VRS Castricum | 28 October | |||
| 2010 | |
VRS Castricum | 2 April | |
VRS Castricum | 21 November | |||
| 2009 | |
VRS Castricum | 2 April | |
VRS Castricum | 11 October | |||
| 2008 | |
VRS Castricum | 28 March | |
VRS Castricum | 3 November | |||
| 2007 | |
VRS Castricum | 1 April | |
VRS Castricum | 30 September | |||
| 2006 | |
VRS Castricum | 4 April | |
VRS Castricum | 26 October | |||
| 2005 | |
VRS Castricum | 27 March | |
VRS Castricum | 30 October | |||
| 2004 | |
VRS Castricum | 3 April | |
VRS Castricum | 2 October | |||
| 2003 | |
VRS Castricum | 26 March | |
VRS Castricum | 3 October | |||
| 2002 | |
VRS Castricum | 31 March | |
VRS Castricum | 13 October | |||
| 2001 | |
VRS Castricum | 30 March | |
VRS Castricum | 18 October | |||
| 2000 | |
VRS Castricum | 3 April | |
VRS Castricum | 24 November | |||
| 1999 | |
VRS Castricum | 29 March | |
VRS Castricum | 5 November | |||
| 1998 | |
VRS Castricum | 31 March | |
VRS Castricum | 10 October | |||
| 1997 | |
VRS Castricum | 9 April | |
VRS Castricum | 18 September | |||
| 1996 | |
VRS Castricum | 8 April | |
VRS Castricum | 11 October | |||
| 1995 | |
VRS Castricum | 5 April | |
VRS Castricum | 1 October | |||
| 1994 | |
VRS Castricum | 6 April | |
VRS Castricum | 18 October | |||
| 1993 | |
VRS Castricum | 3 April | |
VRS Castricum | 17 October | |||
| 1992 | |
VRS Castricum | 8 April | |
VRS Castricum | 4 October | |||
| 1991 | |
VRS Castricum | 30 March | |
VRS Castricum | 22 October | |||
| 1990 | |
VRS Castricum | 2 April | |
VRS Castricum | 2 October | |||
| 1989 | |
VRS Castricum | 28 March | |
VRS Castricum | 9 October | |||
| 1988 | |
VRS Castricum | 18 July | |
VRS Castricum | 22 September | |||
| 1987 | |
VRS Castricum | 10 April | |
VRS Castricum | 20 October | |||
| 1986 | |
VRS Castricum | 17 April | |
VRS Castricum | 14 November | |||
| 1985 | |
VRS Castricum | 1 August | |
VRS Castricum | 13 October | |||
| 1984 | |
VRS Castricum | 31 July | |
VRS Castricum | 8 October | |||
| 1983 | |
VRS Castricum | 1 August | |
VRS Castricum | 22 October | |||
| 1982 | |
VRS Castricum | 5 April | |
VRS Castricum | 3 November | |||
| 1981 | |
VRS Castricum | 5 April | |
VRS Castricum | 17 September | |||
| 1980 | |
VRS Castricum | 31 July | |
VRS Castricum | 10 October | |||
| 1979 | |
VRS Castricum | 1 August | |
VRS Castricum | 15 October | |||
| 1978 | |
VRS Castricum | 1 August | |
VRS Castricum | 13 October | |||
| 1977 | |
VRS Castricum | 16 April | |
VRS Castricum | 7 October | |||
| 1976 | |
VRS Castricum | 14 August | |
VRS Castricum | 17 October | |||
| 1975 | |
VRS Castricum | 6 August | |
VRS Castricum | 1 November | |||
| 1974 | |
VRS Castricum | 19 August | |
VRS Castricum | 14 September | |||
| 1973 | |
VRS Castricum | 28 July | |
VRS Castricum | 15 October | |||
| 1970 | |
VRS Castricum | 13 October | |
VRS Castricum | 13 October | |||
| 1967 | |
VRS Castricum | 16 September | |
VRS Castricum | 16 September | |||
| 1964 | |
VRS Castricum | 8 August | |
VRS Castricum | 8 August | |||
| 1961 | |
VRS Castricum | 1 July | |
VRS Castricum | 1 July |
